The need exists for an improved system for tenderizing meat. A dichotomy exists in the fact that the public demands meat which is tender, yet the lower the fat content of the meat the greater the toughness and the public is becoming increasingly aware that the consumption of fat is unhealthy. In addition to the health advantages in tenderizing low fat meats, there is also an economic advantage because low fat meat is generally less expensive than high fat meat.
Many methods have been used in the past or at least suggested for tenderizing meat. The most common is simple mechanical pounding; but pounding breaks the meat fibers and changes both the texture and appearance of the meat. So-called "aging", which involves storage of the meat at a controlled temperature, e.g. 35.degree.-40.degree. F., for three or four weeks, has also been commonly used, but this type of operation is actually a controlled putrefaction which is expensive and slightly alters the flavor of the meat.
It is also been proposed to treat meat chemically, e.g. with tenderizing enzymes or in a chemical bath, but this type of treatment acts primarily only on the meat surface and tends to degrade the meat texture, i.e. make it "mushy". Other suggested methods include pulse massage and ultrasonic waves introduced in water into which the meat has been submerged, but these methods have proven largely ineffective.
The 1970 U.S. Pat. No. 3,492,688 in the name of Godfrey discloses a method and apparatus for tenderizing meat by the use of an explosive charge which generates and applies a shock front pressure wave propagated through a liquid medium at velocities exceeding the speed of sound. It is stated that the meat may be placed in a protective wrapping such as a flexible bag made of rubber or plastic material, from which the air has been evacuated.
While the principle behind the Godfrey U.S. Pat. No. '928 is sound, the embodiments disclosed and especially the tank and position of the meat in relation to the tank and explosive charge would present serious difficulties in the commercial tenderizing of meat. In the illustrated embodiments the meat would be thrown against the tank walls or the tank cover. Another problem is that in order to have an effective shock wave, a certain minimum explosive force is required; when such a minimum explosive charge is utilized, however, the force is sufficiently great to blow off the top of the container of the Godfrey apparatus. Accordingly, and insofar as is known, the Godfrey system has never achieved actual utilization.